MICROANATOMY

Detailed explanation-1: -Overview. The bronchus in the lungs are lined with hair-like projections called cilia that move microbes and debris up and out of the airways. Scattered throughout the cilia are goblet cells that secrete mucus which helps protect the lining of the bronchus and trap microorganisms.

Detailed explanation-2: -The trachea is also lined with cilia, which sweep fluids and foreign particles out of the airway so that they stay out of the lungs. At its bottom end, the trachea divides into left and right air tubes called bronchi (pronounced: BRAHN-kye), which connect to the lungs.

Detailed explanation-3: -In general, the trachea is lined with ciliated pseudostratified columnar epithelium.

Detailed explanation-4: -The respiratory epithelium in trachea and bronchi is pseudostratified and primarily consists of three main cell types – cilia cells, goblet cells, and basal cells. The ciliated cells are located across the apical surface and facilitate the movement of mucus across the airway tract.

Detailed explanation-5: -All humans have a ‘line of defence’ namely the respiratory epithelium with cilia lining the upper respiratory tract from the posterior third of the nasopharynx to the bronchioles [1].